U.S. Pat. No. 4,865,116 issued Sep. 12, 1989 for a "Continuous Metal Tube Casting Method and Apparatus"--Jeffrey N. Peterson and Robert T. Frost--inventors--now assigned to Showa Electric Wire & Cable Co., Ltd. of Tokyo, Japan, describes and claims a method and system to continuously cast metallic pipe. The method and system of U.S. Pat. No. 4,865,116 comprises essentially two multi-phase, traveling wave levitating assemblies, one located outside the pipe within a heat exchanger and the other located inside the pipe.
In addition to U.S. Pat. No. 4,865,116 there are a number of known prior art patents such as U.S. Pat. No. 4,414,285, issued Nov. 8, 1983 for a "Continuous Metal Casting Method, Apparatus and Product"--H. R. Lowry and Robert T. Frost, inventors, now assigned to Showa Electric Wire & Cable Co., Ltd. of Tokyo, Japan, which employ an electromagnetic levitation and containment method and system for the casting of continuous rod. These prior art patents in conjunction with U.S. Pat. No. 4,865,116 in which they are cited, provide a detailed description of the principals and implementation of the electromagnetic levitation and containment method and system. As a consequence, this disclosure will be limited to a description of the features of the levitator assembly employing a single phase solenoid coil which patentably distinguishes this invention from the previously issued pipe casting U.S. Pat. No. 4,865,116 employing two multi-phase electromagnetic levitating coils.
In addition to the above-noted prior patents and disclosures, such as U.S. Pat. No. 4,414,285, related to the electromagnetic levitation/containment casting of solid rod products, and U.S. Pat. No. 4,865,116 relating to the electromagnetic levitation/containment casting of tubular metal products, such as pipe, using multi-phase inner and outer electromagnetic levitation/containment fields producing coil assemblies, there is a further family of prior patents and disclosures which relate to the use of single phase, standing wave, electromagnetic containment field producing heat exchanger/solenoid coil assemblies in the electromagnetic casting of hollow metal ingots. This family of prior art methods and systems is typified by U.S. Pat. No. 4,126,175--issued Nov. 21, 1978--Z. N. Getselev for "Electromagnetic Mould for the Continuous and Semi-Continuous Casting of Hollow Ingots".